Readthrough acetylcholinesterase is increased in human liver cirrhosis.

Background & Aims: There have been many studies on plasma butyrylcholinesterase in liver dysfunction. However, no data is available about acetylcholinesterase in human cirrhosis, although profound changes have been described in cirrhotic rat models.

Methods: Human serum and liver acetylcholinesterase and its molecular forms were determined enzymatically, after butyrylcholinesterase immunodepletion.

Changes in acetylcholinesterase expression are associated with altered presenilin-1 levels.

We have previously identified presenilin-1 (PS1), the active component of the γ-secretase complex, as an interacting protein of the amyloid-associated enzyme acetylcholinesterase (AChE). In this study, we have explored the consequences of AChE-PS1 interactions. Treatment of SH-SY5Y cells with the AChE-inhibitor tacrine decreased PS1 levels, in parallel with increase in the secretion of amyloid precursor protein APPα, whereas the cholinergic agonist carbachol had no effect on PS1.

Altered levels of acetylcholinesterase in Alzheimer plasma.

Background: Many studies have been conducted in an extensive effort to identify alterations in blood cholinesterase levels as a consequence of disease, including the analysis of acetylcholinesterase (AChE) in plasma. Conventional assays using selective cholinesterase inhibitors have not been particularly successful as excess amounts of butyrylcholinesterase (BuChE) pose a major problem.

Principal Findings: Here we have estimated the levels of AChE activity in human plasma by first immunoprecipitating BuChE and measuring AChE activity in the immunodepleted plasma.